1. Field of the Invention
The present invention relates to a method and system for protecting a starting clutch, and more particularly, to a method and system that provides an estimated temperature for the starting clutch and performs operations for protecting the starting clutch if the estimated temperature exceeds the critical temperature of the clutch.
2. Description of Related Art
In an automatic transmission vehicle, the temperature of a clutch used to control a transmission member generally corresponds to the maximum frictional heat energy of a friction member. In this case, the maximum frictional energy of the friction member is calculated using the maximum transmission torque, relative revolutions per minute (RPM) of components, and transmission time of the control of oil pressure. Further, a generally conventional clutch protecting logic controls the thickness of the friction member plate in order to ensure the clutch so that the temperature calculated from the maximum frictional heat energy of the friction member, which may be generated during the transmission, does not exceed critical temperature of the clutch. Accordingly, the clutch protecting logic generally protects the clutch.
Meanwhile, in an automatic transmission vehicle provided with a starting clutch, the temperature of the starting clutch is sensed by a temperature sensor that senses the temperature of oil dispersed through a friction member plate. If the temperature sensed by the temperature sensor exceeds critical temperature, the starting clutch is protected by conventional clutch protecting logic. However, when the temperature of the starting clutch is sensed using the temperature sensor, the amount of oil flowing on the friction surface of the starting clutch is not sufficient during the slip or locking of the starting clutch. For this reason, it is difficult to effectively sense the temperature of the starting clutch. Further, conventional clutch protecting logic generally only protects the clutch by using the maximum frictional heat energy generated during one time of transmission. Since the starting clutch has characteristic of continuous or repeated slip, cumulative temperature should be detected. However, since the cooling corresponding to the characteristic of the starting clutch is not considered in conventional clutch protecting logic, conventional clutch protecting logic cannot effectively calculate the temperature of the starting clutch. Accordingly, there is a problem in that it is difficult to protect the starting clutch. For this reason, there has not been proposed a starting clutch protecting logic based on the temperature corresponding to the characteristic of the starting clutch.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.